Low Frequency Acoustic Pressure Meaurements Based on a Fabry Perot Refractometer

Rezki, A.; Silvestri, Z.; Wallerand, J-P.; Guianvarc’h, C.; Himbert, M.

doi:10.21014/tc16-2022.008

Cited by 1 publication

(1 citation statement)

References 14 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In contrast to static (absolute) pressure metrology, the measurement of acoustic pressure is based on the pressure derivative of the refractive index rather than its absolute value. In the infrasonic frequency range the system design can follow static pressure metrology approaches quite closely, and we have recently learned of work along these lines [5]. The work we describe in this paper has so far been developed with the audible frequency range in mind.…”

Section: Introductionmentioning

confidence: 99%

Primary sound standard based on dynamic Fabry-Pérot refractometry

Chijioke,

Allen,

Fick

et al. 2024

Proceedings of the 7th IMEKO TC16 Conference on Pressure and Vacuum Measurement

View full text Add to dashboard Cite

We describe an optical sound standard in which the sound pressure is measured by using a high-finesse optical cavity to observe the induced change in the refractive index of the medium (acousto-optic effect). The optical refractive index of a substance varies with density, and for a compressible substance it will therefore vary in time in an acoustic field. To accurately measure the refractive index changes due to acoustic density variations, we enhance the induced optical phase shifts using a high-finesse optical cavity. By tracking the shift in the optical cavity resonance frequency we sensitively track the shift of the refractive index of the cavity medium and thereby the acoustic pressure in the cavity. We perform the optical measurement at standard telecom wavelength (1550 nm), thereby minimizing the cost of the optoelectronic components required. We report initial measurements in an acoustic resonator, comparing the pressure indicated by the optical cavity to the pressure indicated by a condenser microphone, at 1 kHz and 2 kHz acoustic frequencies.

show abstract

Section: Introductionmentioning

confidence: 99%